Tuesday, January 30, 2007

Medtronic 's Wireless ICD Scrutinized

This morning the WSJ reported that allegations were raised by a former Medtronic engineer, Christopher Fuller, regarding their Concerto biventricular implantable defibrillator:

Mr. Fuller, an engineer who had worked on the Concerto device, said he resigned from Medtronic in protest over what he terms "serious issues" regarding "how Medtronic evaluated the Concerto."

Last year, Mr. Fuller contacted the FDA and the offices of the U.S. senators from Minnesota. In one letter to Republican Sen. Norm Coleman, Mr. Fuller wrote that the Concerto device's long-distance telemetry "exhibited instabilities in testing" and that Medtronic "has chosen to ignore the problem."

Medtronic spokesman Rob Clark said the company believes the frequency band used by doctors to monitor patients with the Concerto "is dedicated for these uses and we believe it's extremely stable. We have had no adverse events reported due to the wireless telemetry features of the devices."

Mr. Fuller contends that this instability can "prevent other circuits from behaving properly" and can lead to "excessive" battery depletion or can "burn up" other circuitry in the devices.

We have implanted some of these devices and are unaware of issues to date with the exception of the wireless telemetery having interference issues with surgical xenon headlamps, but await a formal response from Medtronic and the FDA's evaluation.

1 comment:

This is situation seems to be an example of the challenges faced by medical device vendors just getting in to wireless products. Verification of wireless capabilities in particular is problem due to a lack of experience.

Earlier this month the FDA released a draft guidance on wireless medical devices - focusing on risk analysis and verification.

The potential problem with the Concerto could play out like Guidant's low level technical flaws that were only revealed by a rather considerable body of post market data. You can read about the FDA's guidance document here: http://medicalconnectivity.com/2007/01/12.html#a902

About Me

Westby G. Fisher, MD, FACC is a board certified internist, cardiologist, and cardiac electrophysiologist (doctor specializing in heart rhythm disorders) practicing at NorthShore University HealthSystem in Evanston, IL, USA and is a Clinical Associate Professor of Medicine at University of Chicago's Pritzker School of Medicine. He entered the blog-o-sphere in November, 2005.
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